This invention relates to identification marking and, more particularly, relates to means and methods for permanently relating an identification marking with a solid object.
Serial numbers or other identifying markings have been associated with various objects in order to track and identify such objects. For example, motor vehicle engines, firearms, and other items are often required to be produced with serial numbers. The serial numbers are required by licensing and public safety authorities to enable ownership and origin of such items to be documented and followed.
Typically, serial numbers of this type have been produced on a plate attached to the item or been stamped in the item or mold, and thus are visible to the naked eye. Where the item is polymer based, metal identification bearing tags are now inserted at the surface of the item and are, likewise, visible to the naked eye (see, for example, U.S. Pat. No. 5,632,108). In either case, this form of marking an item is subject to corruption, whether by intentional tampering or by environmental factors such wear or corrosion. Since one basic method for ownership and/or origin identification of many items has been by matching of a serial number visible by optical or surface profiling methods to a record, identification can be made nearly impossible in such cases.
Various mechanisms providing more covert systems of identification have been proposed (see, for example, U.S. Pat. Nos. 4,749,847, 4,019,053, 5,511,483, and 4,445,225). These mechanisms, while undoubtedly effective, are of somewhat limited application due to their complexity and therefore expense, lack of adaptability to current common record keeping systems now, and for the foreseeable future, in use, lack of information carrying capacity, and/or imperfect concealment. Further improvement, particularly directed to providing tamper-proof identification that is adaptable to current common systems of identification and record keeping and that is an, integral part of item manufacture, could thus still be utilized.
This invention provides molded or cast objects including remotely detectable identification markers, and methods for tamper-proof identification of solid objects and substantially permanent location of identification indicia in molded or cast objects. The devices and methods of this invention utilize tamper-proof identification means that are readily adaptable to current common systems of identification and record keeping and that are an integral part of object manufacture. The devices and methods are relatively simple to produce and use, thus avoiding undue expense, and provide relatively large information carrying capacity. Markers in accord with this invention, when located in objects, are perfectly optically concealed.
The molded or cast object of this invention is provided with substantially permanent identification marking included within a solid molded or cast portion formed of a first material. A marker having a formation indicative of selected data is located, when the solid portion is molded or cast, so that the marker is entirely surrounded by the first material of the solid portion. The marker includes or is formed from a constituent material having an atomic number greater than any constituent of the first material forming the solid portion of the object.
The marker may be a thin film insert positioned in the mold before molding or casting of the solid portion of the object. For example, a polymer based thin film having the constituent material thereon could be utilized. The constituent material is preferably a noble metal, particularly where the first material of the solid portion includes a metallic constituent.
Where the molded or cast object includes a functional structure, the solid portion having the marker therein is preferably a part of or located adjacent to the functional structure so that any effort to corrupt the marker degrades the functional structure. By the foregoing means, the formation at the marker is remotely detectable (or readable) using, for example, means operable by principals of energy adsorption, while the marker is neither optically visible nor readily physically accessible to a user of the object.
The methods for substantially tamper-proof identification of a molded or cast object include the steps of establishing a formation indicative of selected data at a marker, with the marker or the formation including material having an atomic number greater than any constituent of the base material forming the object in the region of marker location. The marker is located in a mold before the object is molded or cast in the mold so that the marker is entirely surrounded by the first material of the object when molded or cast. Thus, the formation is detectable through the first material of the object by selected means yet the marker is neither optically visible nor readily physically accessible to a user of the object. The marker is preferably located in the mold at a position so that efforts to corrupt the marker will degrade a functional structure of the object.
In the particular case of firearm identification markings (serial numbers, typically), the invention uses methods of identification which do not rely on surface morphology to identify the firearm. The identification marker, or tag, is made from material that is more radio-opaque than the base material of the firearm or portion thereof where installed. In the case of a polymer firearm, any material that has an atomic number greater than that of carbon could be used, though metals would be most effective. In the case of aluminum firearms, any metal that has an atomic number greater than that of aluminum would be most effective. The same basic calculation holds true for steel (iron alloys) or titanium firearms. While the only requirement is that the marker be made of a material which is more radio opaque than the base material, though material with a higher atomic number will provide a marker more readily identifiable in the firearm base material.
It is therefore an object of this invention to provide substantially tamper-proof, and thus permanent, identification for solid objects.
It is another object of this invention to provide markers and methods for tamper-proof identification of solid objects including firearms.
It is another object of this invention to provide markers and methods for tamper-proof identification of solid objects embodying improvements directed to adaptability to current common systems of identification and record keeping and integration with item manufacture.
It is still another object of this invention to provide markers and methods for identification of solid objects wherein location and presence of an identifying marking is not optically detectable.
It is still another object of this invention to provide markers and methods for identification of solid objects wherein location of an identifying marking is selected so that efforts to corrupt the marking diminish utility of the object.
It is yet another object of this invention to provide a molded or cast object with substantially permanent identification marking comprising a solid molded or cast portion formed of a first material, and a marker having a formation thereat indicative of selected data, the marker including at least a constituent material having an atomic number greater than any constituent of the first material, and the marker being located when the solid portion is molded or cast so that the marker is entirely surrounded by the first material of the solid portion.
It is still another object of this invention to provide a marker for molding or casting within a solid object comprising a thin film insert.
It is yet another object of this invention to provide a method for substantially tamper-proof identification of a molded or cast object formed of a first material that includes the steps of establishing a formation indicative of selected data at a marker, at least one of the marker and the formation including material having an atomic number greater than any constituent of the first material, and locating the marker in a mold before the object is molded or cast in the mold so that the marker is entirely surrounded by the first material of the object when molded or cast, whereby the formation is detectable through the first material of the object by selected means but the marker is neither optically visible nor readily physically accessible to a user of the object.
It is still another object of this invention to provide a method for making a molded or cast object including a functional structure at or adjacent to a solid portion, the solid portion formed of a first material, the object having substantially permanent identification marking, the method including the steps of establishing a formation on a thin film marker indicative of selected data, one of the formation and the marker including a constituent material having an atomic number greater than any constituent of the first material, locating the marker in a mold at a position corresponding to the solid portion before the solid portion is molded or cast in the mold, and molding or casting the solid portion in the mold around the marker, whereby the marker is located relative to the functional structure so that an effort to corrupt the marker degrades the functional structure.
With these and other objects in view, which will become apparent to one skilled in the art as the description proceeds, this invention resides in the novel construction, combination, arrangement of parts and method substantially as hereinafter described, and more particularly defined by the appended claims, it being understood that changes in the precise embodiment of the herein disclosed invention are meant to be included as come within the scope of the claims.